Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare a destructive, non-idempotent write; the description adds real context beyond them — that the outcome may be immediate publication or human-review queuing, that a distinct submit token is required, and a warning not to conflate publication with transaction verification. It stops short of covering irreversibility or duplicate-submission behavior that the destructive/non-idempotent hints imply.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.